A simple majority is any value in excess of 50%. In the House, a tie vote
fails. In the Senate, a tie vote may be broken by the Vice President. A
simple majority is also required for a quorum.

A one-fifth vote is required for any vote to be recorded as "yeas" and
"nays" in the journals of each house.

A two-thirds vote is required to pass a constitutional amendment. A
two-thirds vote is required to overturn a presidential veto. In the Senate, a
two-thirds vote is also required to convict on an impeachment.

In the Senate, a three-fifths vote is required to force an end to a
filibuster.